//
// Created by BaiXin on 2025/8/22.
//
# include "iostream"
# include "windows.h"

using namespace std;

void swap(int &x, int &y) {
    if (x == y) return;
    int temp = x;
    x = y;
    y = temp;
}

int main() {
    SetConsoleOutputCP(CP_UTF8);
    int a = 10, b = 20;
    swap(a, b);
    cout << a << "--" << b << endl;
    return 0;
}